Guillermo del Toro's upcoming sci-fi epic Pacific Rim envisions a future where soldiers wield giant mechs to battle titanic extraterrestial monsters. Fitting, Iron Man and Game of Thrones composer Ramin Djawadi was tapped to create an appropriately massive score, and for the film's theme, Djawadi linked up with Tom Morello to bring a hulking, triumphant guitar sound to the track. But the film didn't just inspire the soundtrack – Djawadi and Morello's music also helped sculpt the film's visual aesthetic.

"Guillermo and I were discussing adding a rock element to the score and Tom's unique style and sounds really defined our robots," Djawadi tells Rolling Stone. For Morello, the collaboration was a no-brainer. "When they asked me to put some giant robot riffs and screaming underwater monster licks on the film score, I was all in," Morello says.